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1.
Science ; 264(5158): 556-8, 1994 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-17732740

RESUMEN

High-resolution electron microscopy and lithium-7 nuclear magnetic resonance measurements were carried out for a disordered carbon material, prepared by heat treatment of polyphenylene, in which lithium was stored electrochemically. The nuclear magnetic resonance spectrum suggests the existence of Li(2) covalent molecules in the carbon material. This extra covalent site of lithium storage promises extraordinarily high energy density for secondary batteries.

2.
Eur J Gynaecol Oncol ; 30(2): 155-61, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19480244

RESUMEN

PURPOSE OF INVESTIGATION: The clinical characteristics and long-term prognostic factors of borderline ovarian tumors (BOTs) were evaluated. METHODS: Data from patients who were treated for BOTs in the Kinki District of Japan from 1990 to 2006 were revieved. Two hundred and twenty-two cases were retrospectively investigated for stage, surgical procedure, histopathological features, adjuvant chemotherapy and prognosis. RESULTS: FIGO stages included 212 patients with Stage I disease, three with Stage II and seven with Stage III. One hundred and sixty-nine cases were diagnosed as mucinous tumor, 47 were serous, and six were others. Radical surgery was performed in 136 patients and conservative surgery in 86 patients. Only two patients showed invasive peritoneal implants. Forty patients received adjuvant chemotherapy. The survival rate was 95% at ten-years. Statistical analysis showed that earlier stage, absence of residual tumors, peritoneal implants, ovarian stromal involvement, and negative peritoneal cytology were associated with significantly better overall survival. CONCLUSION: The prognosis of patients with BOT is excellent. There are insufficient data to support a role for aggressive surgery and adjuvant chemotherapy for the possibility of prolonged survival.


Asunto(s)
Neoplasias Ováricas/mortalidad , Adolescente , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/patología , Neoplasias Ováricas/terapia , Pronóstico , Análisis de Supervivencia , Tasa de Supervivencia , Resultado del Tratamiento , Adulto Joven
3.
Domest Anim Endocrinol ; 31(2): 186-96, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16303279

RESUMEN

Prostaglandin F(2alpha) (PGF(2alpha)) is the primary luteolysin in the cow, and luteal endothelin-1 (ET-1) interacts with PGF(2alpha) during the process of luteolysis. In contrast, a developing corpus luteum (CL) is refractory to exogenous administration of PGF(2alpha). Thus, the present study was aimed to investigate the functional relationship between ET-1 and PGF(2alpha) in the mid-CL (PGF(2alpha)-sensitive) and early-CL (PGF(2alpha)-refractory). In the mid-CL model, cows (n = 6/treatment) were assigned to receive one of five types of treatments on day 10 of the estrous cycle: (1) an injection of saline; control, (2) a 500 microg of PGF(2alpha) analogue (sufficient dose to induce luteolytis); full-PG, (3) an intraluteal injection of 0.25 mg ET-1; ET-1, (4) a 125 micro g of PGF(2alpha) (insufficient dose to induce luteolytis); 1/4PG or (5) an intraluteal injection of 0.25 mg ET-1 after administration of a insufficient dose of PGF(2alpha) analogue; 1/4PG/ET. In the early-CL model, cows were assigned to receive one of two types of treatments on day 5 of the estrous cycle: (1) a sufficient dose of PGF(2alpha) analogue; PG (n = 5) or (2) an intraluteal injection ET-1 after a sufficient dose of PGF(2alpha); PG/ET (n = 7). In the mid-CL model, 1/4PG/ET resulted in a rapid reduction of progesterone (P) concentrations similar to that in full-PG from the next day. However, the levels of P in 1/4PG/ET (1.5-2.5 ng/ml) kept significantly higher than that in full-PG (< 0.5 ng/ml). ET-1 or 1/4PG did not decrease plasma P concentrations (4-6 ng/ml). The plasma ET-1 levels increased with the full-PG administration. In the early-CL model, both treatments had no effect on plasma P increase and ET-1 levels. The overall results indicate that the intraluteal ET-1 injection after administration of insufficient dose of PGF(2alpha) induces the depression of P secretion in vivo during the mid luteal phase in the cow, supporting the concept that ET-1 is one of a local mediator of functional luteolysis in the cow. The result further indicates that the early-CL is not only PG-refractory but also ET-1-refractory.


Asunto(s)
Bovinos/fisiología , Cuerpo Lúteo/efectos de los fármacos , Dinoprost/farmacología , Endotelina-1/farmacología , Luteólisis/efectos de los fármacos , Animales , Cloprostenol/farmacología , Cuerpo Lúteo/fisiología , Dinoprost/análogos & derivados , Interacciones Farmacológicas , Endotelina-1/sangre , Ciclo Estral/efectos de los fármacos , Ciclo Estral/fisiología , Femenino , Luteólisis/fisiología , Progesterona/sangre
4.
Transl Psychiatry ; 3: e244, 2013 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-23571809

RESUMEN

The pathogenic mechanisms of Alzheimer's disease (AD) remain largely unknown and clinical trials have not demonstrated significant benefit. Biochemical characterization of AD and its prodromal phase may provide new diagnostic and therapeutic insights. We used targeted metabolomics platform to profile cerebrospinal fluid (CSF) from AD (n=40), mild cognitive impairment (MCI, n=36) and control (n=38) subjects; univariate and multivariate analyses to define between-group differences; and partial least square-discriminant analysis models to classify diagnostic groups using CSF metabolomic profiles. A partial correlation network was built to link metabolic markers, protein markers and disease severity. AD subjects had elevated methionine (MET), 5-hydroxyindoleacetic acid (5-HIAA), vanillylmandelic acid, xanthosine and glutathione versus controls. MCI subjects had elevated 5-HIAA, MET, hypoxanthine and other metabolites versus controls. Metabolite ratios revealed changes within tryptophan, MET and purine pathways. Initial pathway analyses identified steps in several pathways that appear altered in AD and MCI. A partial correlation network showed total tau most directly related to norepinephrine and purine pathways; amyloid-ß (Ab42) was related directly to an unidentified metabolite and indirectly to 5-HIAA and MET. These findings indicate that MCI and AD are associated with an overlapping pattern of perturbations in tryptophan, tyrosine, MET and purine pathways, and suggest that profound biochemical alterations are linked to abnormal Ab42 and tau metabolism. Metabolomics provides powerful tools to map interlinked biochemical pathway perturbations and study AD as a disease of network failure.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/líquido cefalorraquídeo , Biomarcadores/líquido cefalorraquídeo , Estudios de Casos y Controles , Cromatografía Liquida , Disfunción Cognitiva/líquido cefalorraquídeo , Disfunción Cognitiva/metabolismo , Femenino , Humanos , Masculino , Redes y Vías Metabólicas , Metabolómica , Persona de Mediana Edad , Pruebas Neuropsicológicas , Estudios Prospectivos
7.
Acta Paediatr Jpn ; 37(4): 450-7, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7572144

RESUMEN

There is a paucity of knowledge regarding right coronary pulsatile hemodynamics when the right ventricle is under hemodynamic overload as is often the case in pediatric patients with congenital cardiac anomalies. To elucidate the exact mechanisms for the right coronary artery (RCA) to cope with the overload, we studied nine open-chest adult Beagles and analyzed the flow signals of the RCA in relation to independently varied heart rate (pacing) and right ventricular pressure (pulmonary artery banding). Both increased heart rate and right ventricular pressure increased the total volume flow of the RCA. The diastolic over total flow ratio (D/T), however, enlarged on increasing right ventricular pressures while it declined on increasing heart rates. Our data confirmed, as well, that increased flow of RCA on rising heart rate was provided mainly by an increase in systolic phase, while the increase on augmented right ventricular pressure was provided by the increase in diastolic phase. The RCA manages to deliver blood to the right ventricular musculature in two different ways in response to increasing heart rate and right ventricular pressure.


Asunto(s)
Circulación Coronaria , Frecuencia Cardíaca , Presión Ventricular , Animales , Diástole , Perros , Sístole
8.
J Biol Chem ; 275(15): 10831-7, 2000 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-10753877

RESUMEN

Together with a transient accumulation of intracellular cAMP, thyrotropin (TSH) stimulation of the FRTL-5 thyroid cell induces phosphorylation and activation of a cAMP-specific phosphodiesterase (PDE4D3). Here we have investigated the impact of PDE4D3 activation on hormone responsiveness. Stimulation of FRTL-5 cells with TSH caused an increase in PDE activity within 3 min, with a maximal stimulation reached after 5 min. Preincubation with the protein kinase A (PKA) inhibitor H89 or (R(p))-cAMPS, but not with the inactive isomer H85, blocked this activation. Preincubation with PKA inhibitors also blocked the shift in mobility of the PDE4D3 protein. Under these conditions, H89, but not H85, potentiated the cAMP accumulation induced by TSH. Incubation of FRTL-5 cells with the PKA activator 8-(4-chlorophenylthio)adenosine-cAMP caused an increase in PDE activity and a decrease in the endogenous cAMP, confirming the presence of a PKA-PDE feedback loop. MA-10 Leydig tumor cells stably transfected with either a wild type PDE4D3 or a PDE4D3 with mutations in the PKA phosphorylation sites showed an increase in PDE activity when compared with control cells. Human choriogonadotropin or Bt(2)cAMP treatment induced a stimulation of PDE activity in cells transfected with wild type PDE4D3, whereas the activation was absent in mutant- and control-transfected cells. The increase in cAMP accumulation elicited by human choriogonadotropin was reduced in cells transfected with the wild type PDE4D3, but not in cells transfected with the mutant PDE. Rolipram, a specific inhibitor of PDE4, restored the cAMP accumulation in the PDE4D3-transfected cells. These data provide evidence that a rapid activation of PDE4D3 is one of the mechanisms determining the intensity of the cAMP signal.


Asunto(s)
3',5'-AMP Cíclico Fosfodiesterasas/fisiología , AMP Cíclico/metabolismo , Glándula Tiroides/metabolismo , Animales , Células Cultivadas , AMP Cíclico/análogos & derivados , AMP Cíclico/farmacología , Proteínas Quinasas Dependientes de AMP Cíclico/fisiología , Activación Enzimática , Retroalimentación , Humanos , Fosforilación , Ratas , Rolipram/farmacología , Tionucleótidos/farmacología , Tirotropina/farmacología
9.
J Nutr ; 130(12): 2910-4, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11110845

RESUMEN

The effects of dietary restriction of a single essential amino acid (EAA) on insulin-like growth factor-I (IGF-I) and IGF-binding protein (IGFBP)-1 were investigated in rats. Rats were fed experimental diets containing amino acid (AA) mixtures in which the concentrations of all EAA were at levels recommended by the National Research Council (control), in which a single EAA was restricted to 20% of that of the control diets (Leu(-), Lys(-), Met(-) or Thr(-)), or in which the diet was devoid of amino acids (AA(-)). To eliminate the effect of differences in energy intake, rats were fed the mean amount of food as consumed by the AA(-) group on the previous day. Growth was significantly retarded in rats fed diets restricted in just one EAA compared with that of rats fed the control diet, and further growth retardation was observed in rats fed the AA(-) diet. On the other hand, the plasma IGF-I concentrations in the groups with a single EAA restriction or in the AA(-) group were 66% (P: < 0. 05) and 50% (P: < 0.05) of that of the control group, respectively. The effect of any single EAA restriction was not significantly different from that of total AA deprivation. The plasma IGFBP-1 concentration in the control group did not differ from that of rats fed diets with the single EAA restrictions except for methionine restriction, but it was approximately 6-fold greater in the AA(-) group. Differences in plasma IGFBP-1 concentration under these conditions could be explained by differences in hepatic IGFBP-1 mRNA contents. Based on these results, we conclude that restriction of single EAA does not affect IGFBP-1 synthesis in vivo, although the deprivation of a single EAA has been reported to increase IGFBP-1 production in hepatocyte cultures. Our results also indicated that a single EAA restriction decreased IGF-I production but did not affect IGFBP-1 production. The present study suggests that not only plasma IGF-I, but also IGFBP-1, affects the magnitude of growth retardation in vivo.


Asunto(s)
Aminoácidos Esenciales/administración & dosificación , Dieta con Restricción de Proteínas/efectos adversos , Proteínas en la Dieta/farmacología , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Hígado/metabolismo , Aminoácidos Esenciales/metabolismo , Animales , Proteínas en la Dieta/administración & dosificación , Masculino , ARN Mensajero/análisis , Ratas , Ratas Wistar
10.
Jpn J Cancer Res ; 83(11): 1198-203, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1483934

RESUMEN

We have analyzed the genomic structure of the human WT1 gene, one of the recessive oncogenes for Wilms' tumor at chromosome 11p13. By analyses of three cosmids covering the WT1 gene as well as products generated by polymerase chain reaction, cleavage sites for 10 restriction enzymes were mapped in a region of about 80 kb, and the positions of 10 exons were defined. We also mapped two polymorphic sites for TaqI. Our genomic map will be useful to analyze DNA abnormalities sometimes found in the tumors, as well as loss of heterozygosity.


Asunto(s)
Proteínas de Unión al ADN/genética , Genes del Tumor de Wilms/genética , Mapeo Restrictivo , Secuencia de Bases , Cósmidos/genética , ADN de Neoplasias/genética , Desoxirribonucleasas de Localización Especificada Tipo II , Exones/genética , Genoma Humano , Humanos , Intrones/genética , Datos de Secuencia Molecular , Polimorfismo Genético/genética , Proteínas WT1
11.
Anal Chem ; 68(23): 4149-52, 1996 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-21619325

RESUMEN

A new series of methyltrialkylammonium salts with an alkyl chain length (n) longer than the conventional methyltridodecylammonium (MTDDA, n = 12) has been developed, and these materials were examined for use as the ion-sensing component (ligand) in anion-selective electrodes (ISEs). Syntheses of the higher ammoniums with n = 16, 18, and 20 were carried out. In combination with an alcoholic plasticizer, the ammoniums with n = 12, 16, and 18 led to ISEs with fundamental characteristics, such as slope sensitivity, impedance, and time response, that were sufficient for practical applications. Compared with the conventional MTDDA, the ISEs based on the ligands of n = 16 and 18 showed marked improvement in chloride selectivity over both lipophilic and hydrophilic anions, deviating from the Hofmeister regime in some cases. Taking perchlorate as an example, the magnitude of the improvement was a factor of 20 for n = 16 and 15 for n = 18. When the new ISEs were applied to chloride analysis in blood serum, they improved the accuracy by a factor of 2-6. Therefore, the methyltrialkylammonium salts with alkyl chain lengths of 16 and 18 offer definite advantages over the conventional alternative and are strong candidates to become the standard compounds for use in future chloride ISEs.

12.
J Gen Virol ; 74 ( Pt 5): 911-6, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8492098

RESUMEN

The complete nucleotide sequence of the P gene of simian virus 41 (SV41) was determined. The gene was found to be 1406 nucleotides long and to contain a relatively small open reading frame encoding a cysteine-rich V protein with a calculated M(r) of 24076. We have demonstrated that RNA-editing events occur in SV41 P gene transcripts and that the ratio of edited mRNAs to faithfully copied mRNA (P-mRNA:V-mRNA) is about 1:5 at either 24 or 40 h post-infection. The mRNA with two G insertions was capable of encoding a P protein of 395 amino acids with a predicted M(r) of 41,992. A kinetic study of P and V proteins by Western blot analysis showed that in virus-infected cells the amounts of both proteins were almost equal although the V-mRNA was considerably more abundant than the P-mRNA. Alignment of the SV41 P and V proteins with those of nine other paramyxoviruses demonstrated that irregular gaps were present around the RNA-editing sites.


Asunto(s)
Genes Virales , Paramyxoviridae/genética , Edición de ARN , Eliminación de Secuencia , Proteínas Virales/genética , Secuencia de Aminoácidos , Secuencia de Bases , Western Blotting , ADN Viral , Datos de Secuencia Molecular , Paramyxoviridae/clasificación , Filogenia , ARN Viral , Homología de Secuencia de Aminoácido
13.
Pediatr Int ; 42(5): 476-82, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11059534

RESUMEN

BACKGROUND AND METHODS: In order to elucidate the underlying adjusting mechanism of human right coronary arterial (RCA) flow to increased right ventricular pressure (RVP) in children, we recorded RCA flow velocity in 24 pediatric cardiac patients at the orifice of its main trunk at the time of heart catheterization using the Doppler guidewire. RESULTS: The ratio of diastolic flow (DF)/total flow (TF), or the proportion of the DF time integral over a total of one cardiac cycle, had a negative correlation with heart rate (HR; r = -0.58, n = 11) in children with normal right ventricular systolic pressure (RVSP; RVSP < 35 mmHg). In contrast, the DF/TF ratio had a good correlation (r = 0.88, n = 24) with RVSP in all patients under study. The ratio of diastolic area (DA)/total area (TA), defined as the ratio of an area encircled by the aortic pressure curve above and the RVP curve below for diastole, over a total of one cardiac cycle, representing the overall effect of both HR and transcoronary pressure difference, also correlated well (r = 0.89, n = 24) with DF/TF. Total volume flow of the RCA also increased (r= 0.76, n = 24) with increases in RVSP, first by an increase in flow velocity through the RCA, during both systole and diastole, then by widening of the RCA lumen at very high pressures. These changes were initially more dependent on diastole with increasing RVSP because: (i) of a more marked augmentation of flow velocity in diastole compared with systole; and then (ii) of a significant decrease in flow velocity in systole at very high pressures. CONCLUSIONS: We clarify how the RCA manages to increase flow through it at different HR as a function of chronic RVP overload in pediatric cardiac patients.


Asunto(s)
Circulación Coronaria/fisiología , Cardiopatías Congénitas/fisiopatología , Frecuencia Cardíaca , Presión Ventricular , Adolescente , Adulto , Velocidad del Flujo Sanguíneo , Niño , Preescolar , Vasos Coronarios/fisiología , Ecocardiografía Doppler , Corazón/fisiología , Cardiopatías Congénitas/diagnóstico por imagen , Cardiopatías Congénitas/patología , Hemodinámica , Humanos
14.
J Gen Virol ; 72 ( Pt 9): 2289-92, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1654380

RESUMEN

The nucleotide sequences of cDNAs of the simian virus 5 (SV5) nucleoprotein (NP) gene, and the 3' end of the genome and NP gene of SV41 were determined. The open reading frames of the SV5 and SV41 NP genes encode polypeptides with Mrs of 56,582 and 60,575, respectively, values which are consistent with those estimated by SDS-PAGE. The NP of human parainfluenza virus type 2 (hPIV-2) was more closely related to that of SV41 (amino acid sequence identity 70.5%) than that of SV5 (57.0%); the amino acid sequence identity between the NPs of SV41 and SV5 was 63.3%. The sequence of the 3' end of the genome of SV41 showed a high level of similarity to that of hPIV-2, the terminal 18 nucleotides being identical. It is concluded from these findings that SV41 is related most closely to hPIV-2, even though SV5 had been thought to be an animal type of hPIV-2.


Asunto(s)
Cápside/genética , ADN Viral/química , Virus de la Parainfluenza 2 Humana/genética , Respirovirus/genética , Proteínas del Núcleo Viral/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cápside/química , Humanos , Macaca fascicularis , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Virus de la Parainfluenza 2 Humana/clasificación , Respirovirus/clasificación , Programas Informáticos , Células Vero , Proteínas del Núcleo Viral/química
15.
Biosci Biotechnol Biochem ; 63(3): 542-9, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10227140

RESUMEN

1-Aminocyclopropane-1-carboxylic acid (ACC), which is a precursor of ethylene in plants, has never been known to occur in microorganisms. We describe the synthesis of ACC by Penicillium citrinum, purification of ACC synthase [EC 4.4.1.14] and ACC deaminase [EC 4.1.99.4], and their properties. Analyses of P. citrinum culture showed occurrence of ACC in the culture broth and in the cell extract. ACC synthase was purified from cells grown in a medium containing 0.05% L-methionine and ACC deaminase was done from cells incubated in a medium containing 1% 2-aminoisobutyrate. The purified ACC synthase, with a specific activity of 327 milliunit/mg protein, showed a single band of M(r) 48,000 in SDS-polyacrylamide gel electrophoresis. The molecular mass of the native enzyme by gel filtration was 96,000 Da. The ACC synthase had the Km for S-adenosyl-L-methionine of 1.74 mM and kcat of 0.56 s-1 per monomer. The purified ACC deaminase, with a specific activity of 4.7 unit/mg protein, showed one band in SDS-polyacrylamide gel electrophoresis of M(r) 41,000. The molecular mass of the native ACC deaminase was 68,000 Da by gel filtration. The enzyme had a Km for ACC of 4.8 mM and kcat of 3.52 s-1. The presence of 7 mM Cu2+ in alkaline buffer solution was effective for increasing the stability of the ACC deaminase in the process of purification.


Asunto(s)
Aminoácidos Cíclicos , Aminoácidos/metabolismo , Penicillium/metabolismo , Aminoácidos/biosíntesis , Animales , Biotransformación , Liasas de Carbono-Carbono/genética , Liasas de Carbono-Carbono/aislamiento & purificación , Liasas de Carbono-Carbono/metabolismo , Cromatografía DEAE-Celulosa , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Etilenos/metabolismo , Cinética , Liasas/genética , Liasas/aislamiento & purificación , Liasas/metabolismo , Peso Molecular , Organismos Modificados Genéticamente , Penicillium/enzimología , Penicillium/genética , S-Adenosilmetionina/metabolismo
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